UltimateAjax is an ASP.NET server control to provide AJAX callback functionality in your web applications. This control allows you to make web pages more responsive by exchanging data with the server behind the scenes. Every time the user initiates a callback request UltimateAjax control refreshes only its own contents instead of reloading the entire web page as in the case of a regular postback to server. Supports both .NET 1.x and .NET 2.0.